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How to use GROUP BY to concatenate strings in SQL Server?
...S (1,'B',8)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (2,'C',9)
SELECT
[ID],
STUFF((
SELECT ', ' + [Name] + ':' + CAST([Value] AS VARCHAR(MAX))
FROM #YourTable
WHERE (ID = Results.ID)
FOR XML PATH(''),TYPE).value('(./text())[1]','VARCHAR(MAX)')
,1,2,'') AS NameVa...
INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
ALTER TABLE to add a composite primary key
...dexed from left to right.
For example, consider the following queries:
A) SELECT person, place, thing FROM provider WHERE person = 'foo' AND thing = 'bar';
B) SELECT person, place, thing FROM provider WHERE person = 'foo' AND place = 'baz';
C) SELECT person, place, thing FROM provider WHERE person ...
How to debug PDO database queries?
...gt;setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING );
$db->query('SELECT *******');
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SQL statement to select all rows from previous day
I am looking for a good SQL Statement to select all rows from the previous day from one table. The table holds one datetime column. I am using SQL Server 2005.
...
How should I store GUID in MySQL tables?
...above and when I convert them back using the same methods the guid that is selected is not the one that was inserted. What is transforming the guid? All I've done is copied the code from above.
– vsdev
Dec 17 '15 at 14:53
...
No module named MySQLdb
...
Luckily, there is a selection of alternatives, many of which use the same API: Python 3 and MySQL
– Anthony Geoghegan
Mar 24 '15 at 10:07
...
Why would someone use WHERE 1=1 AND in a SQL clause?
...mple code to Greg's answer:
dim sqlstmt as new StringBuilder
sqlstmt.add("SELECT * FROM Products")
sqlstmt.add(" WHERE 1=1")
''// From now on you don't have to worry if you must
''// append AND or WHERE because you know the WHERE is there
If ProductCategoryID <> 0 then
sqlstmt.AppendForm...
Choosing a stand-alone full-text search server: Sphinx or SOLR? [closed]
... Lucene committers.
Sphinx integrates more tightly with RDBMSs, especially MySQL.
Solr can be integrated with Hadoop to build distributed applications
Solr can be integrated with Nutch to quickly build a fully-fledged web search engine with crawler.
Solr can index proprietary formats like Microsoft ...